Temperature control is critical in brewing beer, without it, it is impossible to brew beers properly. One reason for mediocre beers is due to the lack of temperature control. This often leads to producing off flavours caused by the fusel alcohol and esters produced by the yeast. It can also result in fermentation that is too hot, which makes the yeast become sensitive towards alcohol toxicity. This could cause the yeast to die off due to the slight presence of alcohol.
Fermentation of beer can also encounter problems during winter. Yeasts can show signs of stress on cold condition which include sluggish to no fermentation. It can also lead to the finished product to have a bland taste.
Home brewers have to remember that yeasts prefer a specific range of temperature in order to effectively ferment the wort into beer. It is therefore important to always monitor the ambient temperature of the wort at all times using a thermometer.
Keeping a close eye of the temperature of the brew is very critical in creating consistent beer. This is the reason why home brewers need to invest in a good thermometer to be able to achieve just that.